Best bet
Cures clear and rigid, fills a clean break, and stays waterproof once cured.
Reviewed and adjusted by an editor.
Why this answer
- Non-porous and unforgiving — any grease film or fingerprint weakens the joint and stays visible through the glass forever.
- Cures clear and rigid, and stays waterproof.
How to do it
Step by step
- Wash both broken edges with soap and water and let them dry completely — a fingerprint stays visible through the glass.
- Dry-fit the pieces so you know they close without a gap.
- Mix a small amount of clear 2-part epoxy and coat one edge thinly.
- Press together, wipe the squeeze-out, and tape the joint still.
- Let it cure fully before adding water.
Conditions
When the answer changes
If the vase only has to look whole on a shelf, super glue gel is enough for a tight dry break — the glue line can haze. A hairline crack that still holds together seals better with silicone than with a rigid fill. Missing shards are a replacement, not a glue job.
Alternatives
What else works
The answer for a hairline crack that still holds together — it seals rather than reconstructing a shard.
Avoid
What not to use
Avoid
Super glue (CA)
Ruled out here by Water immersion
Fine for a small, tight, dry repair, though the glue line can haze and it is brittle.
Avoid
Contact cement
Contact cement — it needs a surface that lets solvent escape, and the rubbery film simply peels off glass.
Avoid
Spray adhesive
Spray adhesive — a temporary tack for holding a stencil or film, never a bond.
Avoid
Flexible fabric adhesive
Fabric adhesive — it grips through a weave, and there is nothing to grip on glass.
Avoid
Wood glue (PVA)
Wood glue — it dries by soaking into pores, and glass has none.
Avoid
Polyurethane
Anything opaque or expanding — the foamed glue line shows straight through the glass and can't be hidden.
Avoid
Solvent cement
Solvent cement — glass cannot be softened by a solvent, so there is nothing to weld and nothing left in the joint once it evaporates.
Questions
Common questions
- Can a repaired glass vase hold water again?
- Only after a waterproof adhesive has fully cured and the break is a clean fit with no missing glass. If the product is not documented for standing water, or the joint is incomplete, keep the vase dry and treat the repair as decorative.
- Why do fingerprints matter so much on a glass repair?
- Glass has no pores to hide contamination. Oil on a broken edge becomes a weak layer in the joint and stays visible through the glass after the adhesive cures, so both faces need to be washed and fully dry before any glue goes on.
- Is super glue enough for a broken vase?
- It can hold a small, tight, dry break that only has to sit on a shelf. The glue line can haze, and the joint is brittle, so it is a poor choice when the vase will hold water or the break has any gap.
- Can epoxy replace a missing shard of glass?
- It can bridge a tiny chip, but it does not recreate the original glass surface or hide a large gap. A vase with missing pieces is usually a replacement, not a fill.